Pivotal switch-operating assembly



March 29, 1966 J, sun-0 3,243,565

PIVOTAL SWITCH-OPERATING ASSEMBLY Filed July 22, 1964 2 l FIG.1 I0

23 250 INVENT R.

ZQLJWW zz-zz United States Patent 3,243,565 PIVOTAL SWITCH-OPERATINGASSEMBLY Robert J. Sutton, Chicago, Ill., assignor to General ElectricCompany, a corporation of New York Filed July 22, 1964, Ser. No. 384,5034 Claims. (Cl. 200-172) This invention relates to switch-operatingassemblies, and more particularly to such assemblies wherein thestructure is of the type which may be separated from the switch, suchas, for instance, assemblies intended to be included in closure membersand to operate a switch when in closed position.

It is a common expedient, in many structures having closure members, ordoors, to provide a switch which operates when the door is opened so aseither to complete a circuit or open a circuit. Such switches are of theutmost importance in, for instance, appliances such as dishwashers andclothes dryers in order to make sure that the appliance is not operatingwhen the door is opened. Also, in appliances such as dryers and ovens itis highly desirable that, when the door is opened, a lighting circuit becompleted for the benefit of the operator of the appliance.

In recent years, the use of glass in the closure member of appliancessuch as ovens has substantially increased; with this increase, there hascome about the need to be able to turn on a light in the oven withoutopening the oven door so that the operator may view what is liappening.As a result, many oven doors incorporate a peek switch. This structure,as normally provided, causes the closing of the oven door to close thedoor switch in the normal manner (usually to turn off an oven light),but further permits the door switch to be manually released to turn onthe oven light just as though the door were open.

Such arrangements have proven difiicult to design for long life withoutexcessive expense, and it is an object of my invention to provide such aswitch-operating arrangement which is economical to manufacture and hihly effective in operation.

A further, more specific, object of my invention is to provide such astructure by the use of a rigid link member in cooperation with apivoted arm in order to effect the desired movement of the door switchby manual operation.

In one aspect of my invention I provide my structure for use in a hollowdoor which is intended to close against a door frame having aswitch-operating member biased to extend therefrom. On its inner sidethe hollow door has an opening through which the member extends when thedoor is closed.

On the outer side of the door, a manually operable member is pivotallymounted for movement between first and second positions. Within the doorthere is an arm, pivotally mounted and positioned with its free endhearing against the switch-operating member when the door is closed. Arigid link member is pivotally mounted at its one end to the manuallyoperable member within the door, and at its other end to the arm betweenthe ends thereof. In its first position, the manually operable member,through the link, causes the arm to, push the switchoperating membertoward the door frame to its operative position. In its second position,the manually operable member causes the arm to pivot away from the doorframe, and thus permits the switch-operating member to return to itsbiased position.

This arrangement, including the link member, permits use of a switchwhich is very economical, and at the same time operates very easily andreliably.

The subject matter which I regard as my invention is "ice particularlypointed out and distinctly claimed in the concluding portion of thisspecification. My invention, however, both as to organization and methodof operation, together with further objects and advantages thereof, maybest be understood by reference to the following description taken inconjunction with the accompanying drawing.

In the drawing,

FIGURE 1 is a fragmentary side elevational view, partly incross-section, of a door and door frame incorporating the improvedswitch-operating assembly of my invention;

FIGURE 2 is a fragmentary view similar to FIGURE 1, showing themechanism in a different position;

FIGURE 3 is a view along line 3-3 of FIGURE 2: and

FIGURE 4 is a fragmentary plan view of one of the elements shown inFIGURE 3.

Referring now to FIGURE 1, there is shown a door member, generallyindicated at 1, which is made of a pair of sheet metal members 2 and 3having flanges 4 and 5 respectively. The flanges are joined together sothat a hollow space 6 is provided between the surfaces, or panels, 7 and8 which form the actual door. While no appliance is shown, it may beassumed that door 1 is intended to be used as the closure member for anappliance such as an oven. A window section 9 is formed in the door toallow the user of the appliance to see through the door what ishappening inside. The door closes against a door frame generallyindicated at 10. While the entire frame is not shown, it will beunderstood that the frame conventionally forms a substantiallyrectangular opening, and that door 1 is movable between a position inwhich it covers the opening and a position in which it uncovers theopening.

An electric switch, schematically indicated by the numeral 11, isrigidly mounted on the frame 10. Suitable electric leads 12 and 13 maybe provided extending to the switch so as to permit completion of acircuit depending upon the position of a switch-actuating member 14which extends outwardly from the door frame 10. As shown in dottedoutline, a spring 15 may be provided as a part of the switch 11 so as tobias member 14 to the position shown in FIGURE 1. When door 1 is closed,member 14 extends through an opening 16 formed in inner door panel 8.

A leaf spring member 17 has a flat arm 18 thereof rigidly securedagainst the inner surface of door panel 7 of the door. Arm 18 is joinedto a movable arm 19 by a connecting curved portion 20. Portion 20, ineffect, serves as a pivot for arm 19, as will appear more clearlyherebelow. The free end 21 of spring arm 19 is positioned so as to bearagainst the end 22 of member 14.

A member 23 having a manually operable portion 24 extending throughanopening 25 in door part 7 is pivotally secured so that part 24 may beflipped to an up or a down position in the usual manner. Securement ofmember 23 is achieved by providing a U-shaped indentation 26 in part 18of spring 17. Indentation 26 cooperates with the wall 7 to enclose apivot pin 27 formed as a part of member 23 and extending from the mainbody thereof on each side (see FIGURE 3). It will readily be seen thatas handle part 24 is moved up and down, pin 27 will pivot within theenclosure formed by identation 26 and wall 7.

Within space 6 inside the hollow door, member 23 has a body portion 28with an opening 29 formed therein. In the opening there is pivotallysecured the end 30 of a longitudinally rigid link member 31. The linkmember has a necked-down section 32 adjacent its other end (FIGURE 3)which is pivotally secured to an intermediate portion 33 of spring arm19. Link 31 is thus positioned in space 6 with its length extendinggenerally between panels 7 and 8.

It will readily be seen that the distance between pivot points 30 and 32of link 31 is constant, and that end 30 of link 31. is moved in an areabout the center of rotation represented by the pin portion 27 of member23. Consequently, in view of the retention of section 32 within opening34 of spring arm 19, and as the distance of point 30 from wall 7increases during pivoting of member 23, the distance of point 32therefrom must necessarily also increase. This has the ultimate resultof pushing spring arm 19 toward panel 8 by pivoting the arm 19 aboutcurved portion 20 as a pivot point.

This movement of spring arm 19, away from panel 7 and toward panel 8,causes end 21 of spring arm 19 to move from the position shown in FIGURE1 to the position shown in FIGURE 2. Because end 21 bears against theend 22 of member 14, member 14 is pushed in, against the action ofspring 15, to the position shown in FIG- URE 2. This constitutes anexceedingly simple and easy way of transmitting the desired force topush in operat ing member 14- by pivoting motion of handle part 24.There are no camming surfaces to develop high frictional forces; rather,force transmission is through pivoting members.

It will be seen that with the member 24 in the position of FIGURE 2, theoperating member 14 is in the depressed condition when the door isclosed, that is, it operates the switch so that, if the switch controlsa lighting circuit, the lighting circuit is opened when the door isclosed. However, even with the door closed the member 14 may be releasedto permit the lighting circuit to be completed by pivoting the member 24downwardly to the position of FIGURE 1; in this position, member 14assumes the same position it would have if the door were open.

It will also be seen that there is an over-center toggletyperelationship provided. In other words, with the structure in theposition of FIGURE 2, the forces transmitted from member 14 throughspring arm 19 to link 31 tend to cause member 23 to pivot in a clockwisedirection; this maintains member 23 in the position of FIGURE 2, withportion 35 thereof abutting against the inside surface of panel 7. Onthe other hand, when handle 24 is moved up to the position of FIGURE 1,pivot point 30 moves over center, i.e., to the other side of a straightline joining pin 27 and point 32. This results in a transmission offorces from member 14 tending to cause member 23 to pivotcounterclockwise. Consequently, member 14 also helps maintain member 24in the position of FIGURE 1.

Referring now to FIGURES 3 and 4, opening 34 is actually one slot, orline, of a cross-shaped opening 36. Opening 36 also has a slot 37, atsubstantially right angles to, and somewhat longer than, slot 34. Slot34 is formed to be substantially parallel to the axis of opening 29.Link 31 is a wire member bent to the shape best shown in FIGURE 3. Theshape of the link and the shape of opening 36 permit an exceedinglyquick and easy assembly at the factory: link 31 may be inserted in slot37, and then, when the necked-down section 32 is within the opening, thelink may be turned 90 so as to fit within slot 34. In this position itis then a simple matter to spread apart the two ends 38 and 39 of link31 so that they may enter opening 29. Then the ends may be released, andthe spring characteristics of link 31 will cause the ends to approacheach other, either in abutting relationship or adjacent thereto, asshown in FIGURE 3. This makes the assembly of link 31 to member 23 andspring arm 19 a very simple matter, requiring very little time.

It will be understood that, while in accordance with the patent statutesI have described what at present is considered to be the preferredembodiment of my invention, it will be obvious to those skilled in theart that various changes and modifications may be made thereon Withoutdeparting from the invention, and it is therefore intended in theapended claims to cover all such equivalent variations as fall withinthe true spirit and scope of my invention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is:

1. In a device having a switch-operating member biased to extendforwardly from a door frame, and a hollow door arranged to close againstthe frame, the door having an opening on its inner side through whichthe member extends when the door is closed, the improvement comprismgz(a) a pivotally mounted manually-operable member extending from theouter side of said door and movable between first and second positions;

(b) an arm pivotally mounted within said door and positioned with itsfree end bearing against said switch-operating member when said door isclosed;

(0) and a rigid link member pivotally mounted at its one end to saidmanually operable member and at its other end to said arm intermediatethe ends thereof, said manually operable member in its first positioncausing said arm to push said switchoperating member toward said doorframe to its operative position, said manually operable member in itssecond position causing said arm to pivot away from said door frame andpermit said switchoperating member to return to its biased position.

2. The device defined in claim 1 wherein said arm is a spring whichpivots by deforming about one end thereof which is secured to said door.

3. The device defined in claim 1 wherein said link transmits force fromsaid switch-operating member to maintain said manually operable memberin its first position when said manually operable member is in thatposition, said link passing over center so as to transmit force fromsaid switch-operating member tending to keep said manually operablemember in its second position when said manually operable member is inthat position.

4. The apparatus defined in claim 1 wherein said link member is formedof a single continuous piece of wire having its two ends aligned witheach other to form one end of said link, and having a necked-downportion forming the other end thereof, said arm having a cross-shapedopening formed therein with a longer and a shorter slot, said manuallyoperable member having an opening therein substantially parallel to saidshorter slot and within which said aligned ends of said wire arereceived to provide the pivotal mounting for said link member.

References Cited by the Examiner UNITED STATES PATENTS 2,150,013 3/1939Von Hoorn 200-172 X KATHLEEN H. CLAFFY, Primary Examiner.

H. O. JONES, Assistant Examiner'

1. IN A DEVICE HAVING A SWITCH-OPERATING MEMBER BIASED TO EXTENDFORWARDLY FROM THE DOOR FRAME, AND A HOLLOW DOOR ARRANGED TO CLOSEAGAINST THE FRAME, THE DOOR HAVING AN OPENING ON ITS INNER SIDE THROUGHWHICH THE MEMBER EXTENDS WHEN THE DOOR IS CLOSED, THE IMPROVEMENTCOMPRISING: (A) A PIVOTALLY MOUNTED MANUALLY-OPERABLE MEMBER EXTENDINGFROM THE OUTER SIDE OF SAID DOOR AND MOVABLE BETWEEN FIRST AND SECONDPOSITIONS; (B) AN ARM PIVOTALLY MOUNTED WITHIN SAID DOOR AND POSITIONEDWITH ITS FREE END BEARING AGAINST SAID SWITCH-OPERATING MEMBER WHEN SAIDDOOR IS CLOSED; (C) AND A RIGID LINK MEMBER PIVOTALLY MOUNTED AT ITS ONEEND TO SAID MANUALLY OPERABLE MEMBER AND AT ITS OTHER END TO SAID ARMINTERMEDIATE THE ENDS THEREOF, SAID MANUALLY OPERABLE MEMBER IN ITSFIRST POSITION CAUSING SAID ARM TO PUSH SAID SWITCHOPERATING MEMBERTOWARD SAID DOOR FRAME TO ITS OPERATIVE POSITION, SAID MANUALLY OPERABLEMEMBER IN ITS SECOND POSITION CAUSING SAID ARM TO PIVOT AWAY FROM SAIDDOOR FRAME AND PERMIT SAID SWITCHOPERATING MEMBER TO RETURN TO ITSBIASED POSITION.